If you stand before San Pietro in Montorio and look down from the spot where St. Peter was crucified, you will see, rounding up in the low-lying heart of the city, a dome, white, huge, uncrowned, standing out from the darker buildings round it like an enormous mother-of-pearl shell, softly iridescent, yet, when storm is in the air, taking on a grey and deathlike hue. That is the Pantheon, and thus it has stood, reflecting every mood of the Roman sky, since the days of Hadrian, who became Emperor in the year 117. Hadrian built the magic dome, but it is not his name that stands out in the gigantic lettering on the pediment over the portico. Ninety years before his time, Marcus Agrippa, the intimate friend and (for his sins!) the son-in-law of Augustus, erected a magnificent temple close to the Baths which still bear his name in the Campus Martius, the field of which my brother has told the touching story in “Ave Roma Immortalis.” Agrippa must have forgotten to properly propitiate the gods; we moderns should say that he “had no luck,” for his gorgeous temple was soon struck by lightning and presented a forlorn appearance when Hadrian, that enthusiastic builder, decided to restore it. This he did on his usual princely scale; when he had done with it, the Pantheon (properly “Pantheum,” “all-holy”) must indeed have dazzled the eyes of the beholders, for the dome was entirely covered with tiles of gilt bronze that under the rays of the sun made it seem a second sun that had come to rest on earth. The gilt tiles were stripped off in 663 by a greedy little Emperor, Constans II, who took them away to Syracuse, whence the Saracens successfully looted them a few years afterwards. So the thing that looks like mother-of-pearl is really only covered with sheets of lead—but even lead, when the heavens have looked on it long enough, may become a thing of life and beauty. When Hadrian had finished his building there was nothing left of Agrippa’s original one except the portico; but Hadrian, with rare moderation, left the original founder’s name on that. The Pantheon, which is called by archæologists “the most perfect pagan monument in Rome,” seems to have been, in its beginnings, unfortunate, for only sixty-four years after Hadrian’s death it again stood sadly in need of repair, if we may believe the magniloquent inscription left on its front by Septimus Severus and his son, Caracalla, when they had carried out their pious designs of further restoration.